Final Cut Pro X Share to DVD playback has glitches

I'm new to non linear editing. Just purchased Final Cut Pro X; I'm shooting baseball footage and my edits are fairly simple. I'm shooting with a Canon 5D Mark II, importing to Apple Pro Res, and my computer is an iMac 2.8 GHz Intel Core i7 with OPTIARC DVD RW AD-5680H disc drive.
When I finish my project I go to Share-DVD and everything seems to be working OK. When I put the finished DVD in a DVD player I get an occasional glitch where the video and audio freezes and then resumes after dropping several frames - sometimes 2 or 3 seconds of video. Everything looks fine in FCPX. The problems usually occur toward the end of the DVD. These videos are usually 15 to 20 minutes long. Has anyone had a similar experience? I've shot 6 games so far and this has happened with every DVD I've produced. Thanks in advance to anyone who could share their insight.